[Ximian]

Originally Posted by Boomer 2019

Rotors do not need "prepping" in any way when changing from one brand or type of pad to another. In most cases the pads themselves need "bedding in" prior to taking them to a track though. Be sure to read and follow the instructions that come with them. In the case of the Cobalt pads however, they do not require "bedding in". They can be installed, and driven directly onto the track.

I wouldn't give advice like this without caveats. The rotors themselves don't need prepping, but they certainly have a layer of pad material that might not be compatible with your new or used pads. Taking a few seconds to wipe the rotors clean with a paper towel goes a long way.

PFC and Cobalt Friction pads don't need much bedding in, but CarboTech pads do benefit from it and need a layer of compatible material to get them working well. Abrasive endurance pads put their own layer of pad material down quickly when they're cold but sprint compounds (e.g. XP20 and up) are more sensitive. There are a few other compounds that I've heard need a clean rotor surface prior to bedding in but I don't have firsthand experience with them.

[Triton88]

Took the tires off to check the inside pads, plenty of pad life left after ~180 miles on track.

i noticed the rear rotors were developing a slight discoloration around the outside, they felt smooth to the touch so not a groove being generated, should i be worried?

[Ximian]

Originally Posted by Triton88

i noticed the rear rotors were developing a slight discoloration around the outside, they felt smooth to the touch so not a groove being generated, should i be worried?

No.